contrib/file/src/readelf.c

   1 /*
   2  * Copyright (c) Christos Zoulas 2003.
   3  * All Rights Reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice immediately at the beginning of the file, without modification,
  10  *    this list of conditions, and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  19  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27 #include "file.h"
  28
  29 #ifndef lint
  30 FILE_RCSID("@(#)$File: readelf.c,v 1.90 2011/08/23 08:01:12 christos Exp $")
  31 #endif
  32
  33 #ifdef BUILTIN_ELF
  34 #include <string.h>
  35 #include <ctype.h>
  36 #include <stdlib.h>
  37 #ifdef HAVE_UNISTD_H
  38 #include <unistd.h>
  39 #endif
  40
  41 #include "readelf.h"
  42 #include "magic.h"
  43
  44 #ifdef  ELFCORE
  45 private int dophn_core(struct magic_set *, int, int, int, off_t, int, size_t,
  46     off_t, int *);
  47 #endif
  48 private int dophn_exec(struct magic_set *, int, int, int, off_t, int, size_t,
  49     off_t, int *, int);
  50 private int doshn(struct magic_set *, int, int, int, off_t, int, size_t,
  51     off_t, int *, int);
  52 private size_t donote(struct magic_set *, void *, size_t, size_t, int,
  53     int, size_t, int *);
  54
  55 #define ELF_ALIGN(a)    ((((a) + align - 1) / align) * align)
  56
  57 #define isquote(c) (strchr("'\"`", (c)) != NULL)
  58
  59 private uint16_t getu16(int, uint16_t);
  60 private uint32_t getu32(int, uint32_t);
  61 private uint64_t getu64(int, uint64_t);
  62
  63 private uint16_t
  64 getu16(int swap, uint16_t value)
  65 {
  66         union {
  67                 uint16_t ui;
  68                 char c[2];
  69         } retval, tmpval;
  70
  71         if (swap) {
  72                 tmpval.ui = value;
  73
  74                 retval.c[0] = tmpval.c[1];
  75                 retval.c[1] = tmpval.c[0];
  76
  77                 return retval.ui;
  78         } else
  79                 return value;
  80 }
  81
  82 private uint32_t
  83 getu32(int swap, uint32_t value)
  84 {
  85         union {
  86                 uint32_t ui;
  87                 char c[4];
  88         } retval, tmpval;
  89
  90         if (swap) {
  91                 tmpval.ui = value;
  92
  93                 retval.c[0] = tmpval.c[3];
  94                 retval.c[1] = tmpval.c[2];
  95                 retval.c[2] = tmpval.c[1];
  96                 retval.c[3] = tmpval.c[0];
  97
  98                 return retval.ui;
  99         } else
 100                 return value;
 101 }
 102
 103 private uint64_t
 104 getu64(int swap, uint64_t value)
 105 {
 106         union {
 107                 uint64_t ui;
 108                 char c[8];
 109         } retval, tmpval;
 110
 111         if (swap) {
 112                 tmpval.ui = value;
 113
 114                 retval.c[0] = tmpval.c[7];
 115                 retval.c[1] = tmpval.c[6];
 116                 retval.c[2] = tmpval.c[5];
 117                 retval.c[3] = tmpval.c[4];
 118                 retval.c[4] = tmpval.c[3];
 119                 retval.c[5] = tmpval.c[2];
 120                 retval.c[6] = tmpval.c[1];
 121                 retval.c[7] = tmpval.c[0];
 122
 123                 return retval.ui;
 124         } else
 125                 return value;
 126 }
 127
 128 #define elf_getu16(swap, value) getu16(swap, value)
 129 #define elf_getu32(swap, value) getu32(swap, value)
 130 #ifdef USE_ARRAY_FOR_64BIT_TYPES
 131 # define elf_getu64(swap, array) \
 132         ((swap ? ((uint64_t)elf_getu32(swap, array[0])) << 32 : elf_getu32(swap, array[0])) + \
 133          (swap ? elf_getu32(swap, array[1]) : ((uint64_t)elf_getu32(swap, array[1]) << 32)))
 134 #else
 135 # define elf_getu64(swap, value) getu64(swap, value)
 136 #endif
 137
 138 #define xsh_addr        (clazz == ELFCLASS32                    \
 139                          ? (void *) &sh32                       \
 140                          : (void *) &sh64)
 141 #define xsh_sizeof      (clazz == ELFCLASS32                    \
 142                          ? sizeof sh32                          \
 143                          : sizeof sh64)
 144 #define xsh_size        (clazz == ELFCLASS32                    \
 145                          ? elf_getu32(swap, sh32.sh_size)       \
 146                          : elf_getu64(swap, sh64.sh_size))
 147 #define xsh_offset      (off_t)(clazz == ELFCLASS32             \
 148                          ? elf_getu32(swap, sh32.sh_offset)     \
 149                          : elf_getu64(swap, sh64.sh_offset))
 150 #define xsh_type        (clazz == ELFCLASS32                    \
 151                          ? elf_getu32(swap, sh32.sh_type)       \
 152                          : elf_getu32(swap, sh64.sh_type))
 153 #define xph_addr        (clazz == ELFCLASS32                    \
 154                          ? (void *) &ph32                       \
 155                          : (void *) &ph64)
 156 #define xph_sizeof      (clazz == ELFCLASS32                    \
 157                          ? sizeof ph32                          \
 158                          : sizeof ph64)
 159 #define xph_type        (clazz == ELFCLASS32                    \
 160                          ? elf_getu32(swap, ph32.p_type)        \
 161                          : elf_getu32(swap, ph64.p_type))
 162 #define xph_offset      (off_t)(clazz == ELFCLASS32             \
 163                          ? elf_getu32(swap, ph32.p_offset)      \
 164                          : elf_getu64(swap, ph64.p_offset))
 165 #define xph_align       (size_t)((clazz == ELFCLASS32           \
 166                          ? (off_t) (ph32.p_align ?              \
 167                             elf_getu32(swap, ph32.p_align) : 4) \
 168                          : (off_t) (ph64.p_align ?              \
 169                             elf_getu64(swap, ph64.p_align) : 4)))
 170 #define xph_filesz      (size_t)((clazz == ELFCLASS32           \
 171                          ? elf_getu32(swap, ph32.p_filesz)      \
 172                          : elf_getu64(swap, ph64.p_filesz)))
 173 #define xnh_addr        (clazz == ELFCLASS32                    \
 174                          ? (void *) &nh32                       \
 175                          : (void *) &nh64)
 176 #define xph_memsz       (size_t)((clazz == ELFCLASS32           \
 177                          ? elf_getu32(swap, ph32.p_memsz)       \
 178                          : elf_getu64(swap, ph64.p_memsz)))
 179 #define xnh_sizeof      (clazz == ELFCLASS32                    \
 180                          ? sizeof nh32                          \
 181                          : sizeof nh64)
 182 #define xnh_type        (clazz == ELFCLASS32                    \
 183                          ? elf_getu32(swap, nh32.n_type)        \
 184                          : elf_getu32(swap, nh64.n_type))
 185 #define xnh_namesz      (clazz == ELFCLASS32                    \
 186                          ? elf_getu32(swap, nh32.n_namesz)      \
 187                          : elf_getu32(swap, nh64.n_namesz))
 188 #define xnh_descsz      (clazz == ELFCLASS32                    \
 189                          ? elf_getu32(swap, nh32.n_descsz)      \
 190                          : elf_getu32(swap, nh64.n_descsz))
 191 #define prpsoffsets(i)  (clazz == ELFCLASS32                    \
 192                          ? prpsoffsets32[i]                     \
 193                          : prpsoffsets64[i])
 194 #define xcap_addr       (clazz == ELFCLASS32                    \
 195                          ? (void *) &cap32                      \
 196                          : (void *) &cap64)
 197 #define xcap_sizeof     (clazz == ELFCLASS32                    \
 198                          ? sizeof cap32                         \
 199                          : sizeof cap64)
 200 #define xcap_tag        (clazz == ELFCLASS32                    \
 201                          ? elf_getu32(swap, cap32.c_tag)        \
 202                          : elf_getu64(swap, cap64.c_tag))
 203 #define xcap_val        (clazz == ELFCLASS32                    \
 204                          ? elf_getu32(swap, cap32.c_un.c_val)   \
 205                          : elf_getu64(swap, cap64.c_un.c_val))
 206
 207 #ifdef ELFCORE
 208 /*
 209  * Try larger offsets first to avoid false matches
 210  * from earlier data that happen to look like strings.
 211  */
 212 static const size_t     prpsoffsets32[] = {
 213 #ifdef USE_NT_PSINFO
 214         104,            /* SunOS 5.x (command line) */
 215         88,             /* SunOS 5.x (short name) */
 216 #endif /* USE_NT_PSINFO */
 217
 218         100,            /* SunOS 5.x (command line) */
 219         84,             /* SunOS 5.x (short name) */
 220
 221         44,             /* Linux (command line) */
 222         28,             /* Linux 2.0.36 (short name) */
 223
 224         8,              /* FreeBSD */
 225 };
 226
 227 static const size_t     prpsoffsets64[] = {
 228 #ifdef USE_NT_PSINFO
 229         152,            /* SunOS 5.x (command line) */
 230         136,            /* SunOS 5.x (short name) */
 231 #endif /* USE_NT_PSINFO */
 232
 233         136,            /* SunOS 5.x, 64-bit (command line) */
 234         120,            /* SunOS 5.x, 64-bit (short name) */
 235
 236         56,             /* Linux (command line) */
 237         40,             /* Linux (tested on core from 2.4.x, short name) */
 238
 239         16,             /* FreeBSD, 64-bit */
 240 };
 241
 242 #define NOFFSETS32      (sizeof prpsoffsets32 / sizeof prpsoffsets32[0])
 243 #define NOFFSETS64      (sizeof prpsoffsets64 / sizeof prpsoffsets64[0])
 244
 245 #define NOFFSETS        (clazz == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64)
 246
 247 /*
 248  * Look through the program headers of an executable image, searching
 249  * for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE" or
 250  * "FreeBSD"; if one is found, try looking in various places in its
 251  * contents for a 16-character string containing only printable
 252  * characters - if found, that string should be the name of the program
 253  * that dropped core.  Note: right after that 16-character string is,
 254  * at least in SunOS 5.x (and possibly other SVR4-flavored systems) and
 255  * Linux, a longer string (80 characters, in 5.x, probably other
 256  * SVR4-flavored systems, and Linux) containing the start of the
 257  * command line for that program.
 258  *
 259  * SunOS 5.x core files contain two PT_NOTE sections, with the types
 260  * NT_PRPSINFO (old) and NT_PSINFO (new).  These structs contain the
 261  * same info about the command name and command line, so it probably
 262  * isn't worthwhile to look for NT_PSINFO, but the offsets are provided
 263  * above (see USE_NT_PSINFO), in case we ever decide to do so.  The
 264  * NT_PRPSINFO and NT_PSINFO sections are always in order and adjacent;
 265  * the SunOS 5.x file command relies on this (and prefers the latter).
 266  *
 267  * The signal number probably appears in a section of type NT_PRSTATUS,
 268  * but that's also rather OS-dependent, in ways that are harder to
 269  * dissect with heuristics, so I'm not bothering with the signal number.
 270  * (I suppose the signal number could be of interest in situations where
 271  * you don't have the binary of the program that dropped core; if you
 272  * *do* have that binary, the debugger will probably tell you what
 273  * signal it was.)
 274  */
 275
 276 #define OS_STYLE_SVR4           0
 277 #define OS_STYLE_FREEBSD        1
 278 #define OS_STYLE_NETBSD         2
 279
 280 private const char os_style_names[][8] = {
 281         "SVR4",
 282         "FreeBSD",
 283         "NetBSD",
 284 };
 285
 286 #define FLAGS_DID_CORE          0x01
 287 #define FLAGS_DID_NOTE          0x02
 288 #define FLAGS_DID_BUILD_ID      0x04
 289 #define FLAGS_DID_CORE_STYLE    0x08
 290 #define FLAGS_IS_CORE           0x10
 291
 292 private int
 293 dophn_core(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
 294     int num, size_t size, off_t fsize, int *flags)
 295 {
 296         Elf32_Phdr ph32;
 297         Elf64_Phdr ph64;
 298         size_t offset;
 299         unsigned char nbuf[BUFSIZ];
 300         ssize_t bufsize;
 301
 302         if (size != xph_sizeof) {
 303                 if (file_printf(ms, ", corrupted program header size") == -1)
 304                         return -1;
 305                 return 0;
 306         }
 307
 308         /*
 309          * Loop through all the program headers.
 310          */
 311         for ( ; num; num--) {
 312                 if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
 313                         file_badseek(ms);
 314                         return -1;
 315                 }
 316                 if (read(fd, xph_addr, xph_sizeof) == -1) {
 317                         file_badread(ms);
 318                         return -1;
 319                 }
 320                 off += size;
 321
 322                 if (xph_offset > fsize) {
 323                         /* Perhaps warn here */
 324                         continue;
 325                 }
 326
 327                 if (xph_type != PT_NOTE)
 328                         continue;
 329
 330                 /*
 331                  * This is a PT_NOTE section; loop through all the notes
 332                  * in the section.
 333                  */
 334                 if (lseek(fd, xph_offset, SEEK_SET) == (off_t)-1) {
 335                         file_badseek(ms);
 336                         return -1;
 337                 }
 338                 bufsize = read(fd, nbuf,
 339                     ((xph_filesz < sizeof(nbuf)) ? xph_filesz : sizeof(nbuf)));
 340                 if (bufsize == -1) {
 341                         file_badread(ms);
 342                         return -1;
 343                 }
 344                 offset = 0;
 345                 for (;;) {
 346                         if (offset >= (size_t)bufsize)
 347                                 break;
 348                         offset = donote(ms, nbuf, offset, (size_t)bufsize,
 349                             clazz, swap, 4, flags);
 350                         if (offset == 0)
 351                                 break;
 352
 353                 }
 354         }
 355         return 0;
 356 }
 357 #endif
 358
 359 private size_t
 360 donote(struct magic_set *ms, void *vbuf, size_t offset, size_t size,
 361     int clazz, int swap, size_t align, int *flags)
 362 {
 363         Elf32_Nhdr nh32;
 364         Elf64_Nhdr nh64;
 365         size_t noff, doff;
 366 #ifdef ELFCORE
 367         int os_style = -1;
 368 #endif
 369         uint32_t namesz, descsz;
 370         unsigned char *nbuf = CAST(unsigned char *, vbuf);
 371
 372         (void)memcpy(xnh_addr, &nbuf[offset], xnh_sizeof);
 373         offset += xnh_sizeof;
 374
 375         namesz = xnh_namesz;
 376         descsz = xnh_descsz;
 377         if ((namesz == 0) && (descsz == 0)) {
 378                 /*
 379                  * We're out of note headers.
 380                  */
 381                 return (offset >= size) ? offset : size;
 382         }
 383
 384         if (namesz & 0x80000000) {
 385             (void)file_printf(ms, ", bad note name size 0x%lx",
 386                 (unsigned long)namesz);
 387             return offset;
 388         }
 389
 390         if (descsz & 0x80000000) {
 391             (void)file_printf(ms, ", bad note description size 0x%lx",
 392                 (unsigned long)descsz);
 393             return offset;
 394         }
 395
 396
 397         noff = offset;
 398         doff = ELF_ALIGN(offset + namesz);
 399
 400         if (offset + namesz > size) {
 401                 /*
 402                  * We're past the end of the buffer.
 403                  */
 404                 return doff;
 405         }
 406
 407         offset = ELF_ALIGN(doff + descsz);
 408         if (doff + descsz > size) {
 409                 /*
 410                  * We're past the end of the buffer.
 411                  */
 412                 return (offset >= size) ? offset : size;
 413         }
 414
 415         if ((*flags & (FLAGS_DID_NOTE|FLAGS_DID_BUILD_ID)) ==
 416             (FLAGS_DID_NOTE|FLAGS_DID_BUILD_ID))
 417                 goto core;
 418
 419         if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
 420             xnh_type == NT_GNU_VERSION && descsz == 16) {
 421                 uint32_t desc[4];
 422                 (void)memcpy(desc, &nbuf[doff], sizeof(desc));
 423
 424                 if (file_printf(ms, ", for GNU/") == -1)
 425                         return size;
 426                 switch (elf_getu32(swap, desc[0])) {
 427                 case GNU_OS_LINUX:
 428                         if (file_printf(ms, "Linux") == -1)
 429                                 return size;
 430                         break;
 431                 case GNU_OS_HURD:
 432                         if (file_printf(ms, "Hurd") == -1)
 433                                 return size;
 434                         break;
 435                 case GNU_OS_SOLARIS:
 436                         if (file_printf(ms, "Solaris") == -1)
 437                                 return size;
 438                         break;
 439                 case GNU_OS_KFREEBSD:
 440                         if (file_printf(ms, "kFreeBSD") == -1)
 441                                 return size;
 442                         break;
 443                 case GNU_OS_KNETBSD:
 444                         if (file_printf(ms, "kNetBSD") == -1)
 445                                 return size;
 446                         break;
 447                 default:
 448                         if (file_printf(ms, "<unknown>") == -1)
 449                                 return size;
 450                 }
 451                 if (file_printf(ms, " %d.%d.%d", elf_getu32(swap, desc[1]),
 452                     elf_getu32(swap, desc[2]), elf_getu32(swap, desc[3])) == -1)
 453                         return size;
 454                 *flags |= FLAGS_DID_NOTE;
 455                 return size;
 456         }
 457
 458         if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
 459             xnh_type == NT_GNU_BUILD_ID && (descsz == 16 || descsz == 20)) {
 460             uint32_t desc[5], i;
 461             if (file_printf(ms, ", BuildID[%s]=0x", descsz == 16 ? "md5/uuid" :
 462                 "sha1") == -1)
 463                     return size;
 464             (void)memcpy(desc, &nbuf[doff], descsz);
 465             for (i = 0; i < descsz >> 2; i++)
 466                 if (file_printf(ms, "%.8x", desc[i]) == -1)
 467                     return size;
 468             *flags |= FLAGS_DID_BUILD_ID;
 469         }
 470
 471         if (namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0 &&
 472             xnh_type == NT_NETBSD_VERSION && descsz == 4) {
 473                 uint32_t desc;
 474                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 475                 desc = elf_getu32(swap, desc);
 476
 477                 if (file_printf(ms, ", for NetBSD") == -1)
 478                         return size;
 479                 /*
 480                  * The version number used to be stuck as 199905, and was thus
 481                  * basically content-free.  Newer versions of NetBSD have fixed
 482                  * this and now use the encoding of __NetBSD_Version__:
 483                  *
 484                  *      MMmmrrpp00
 485                  *
 486                  * M = major version
 487                  * m = minor version
 488                  * r = release ["",A-Z,Z[A-Z] but numeric]
 489                  * p = patchlevel
 490                  */
 491                 if (desc > 100000000U) {
 492                         uint32_t ver_patch = (desc / 100) % 100;
 493                         uint32_t ver_rel = (desc / 10000) % 100;
 494                         uint32_t ver_min = (desc / 1000000) % 100;
 495                         uint32_t ver_maj = desc / 100000000;
 496
 497                         if (file_printf(ms, " %u.%u", ver_maj, ver_min) == -1)
 498                                 return size;
 499                         if (ver_rel == 0 && ver_patch != 0) {
 500                                 if (file_printf(ms, ".%u", ver_patch) == -1)
 501                                         return size;
 502                         } else if (ver_rel != 0) {
 503                                 while (ver_rel > 26) {
 504                                         if (file_printf(ms, "Z") == -1)
 505                                                 return size;
 506                                         ver_rel -= 26;
 507                                 }
 508                                 if (file_printf(ms, "%c", 'A' + ver_rel - 1)
 509                                     == -1)
 510                                         return size;
 511                         }
 512                 }
 513                 *flags |= FLAGS_DID_NOTE;
 514                 return size;
 515         }
 516
 517         if (namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0 &&
 518             xnh_type == NT_FREEBSD_VERSION && descsz == 4) {
 519                 uint32_t desc;
 520                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 521                 desc = elf_getu32(swap, desc);
 522                 if (file_printf(ms, ", for FreeBSD") == -1)
 523                         return size;
 524
 525                 /*
 526                  * Contents is __FreeBSD_version, whose relation to OS
 527                  * versions is defined by a huge table in the Porter's
 528                  * Handbook.  This is the general scheme:
 529                  *
 530                  * Releases:
 531                  *      Mmp000 (before 4.10)
 532                  *      Mmi0p0 (before 5.0)
 533                  *      Mmm0p0
 534                  *
 535                  * Development branches:
 536                  *      Mmpxxx (before 4.6)
 537                  *      Mmp1xx (before 4.10)
 538                  *      Mmi1xx (before 5.0)
 539                  *      M000xx (pre-M.0)
 540                  *      Mmm1xx
 541                  *
 542                  * M = major version
 543                  * m = minor version
 544                  * i = minor version increment (491000 -> 4.10)
 545                  * p = patchlevel
 546                  * x = revision
 547                  *
 548                  * The first release of FreeBSD to use ELF by default
 549                  * was version 3.0.
 550                  */
 551                 if (desc == 460002) {
 552                         if (file_printf(ms, " 4.6.2") == -1)
 553                                 return size;
 554                 } else if (desc < 460100) {
 555                         if (file_printf(ms, " %d.%d", desc / 100000,
 556                             desc / 10000 % 10) == -1)
 557                                 return size;
 558                         if (desc / 1000 % 10 > 0)
 559                                 if (file_printf(ms, ".%d", desc / 1000 % 10)
 560                                     == -1)
 561                                         return size;
 562                         if ((desc % 1000 > 0) || (desc % 100000 == 0))
 563                                 if (file_printf(ms, " (%d)", desc) == -1)
 564                                         return size;
 565                 } else if (desc < 500000) {
 566                         if (file_printf(ms, " %d.%d", desc / 100000,
 567                             desc / 10000 % 10 + desc / 1000 % 10) == -1)
 568                                 return size;
 569                         if (desc / 100 % 10 > 0) {
 570                                 if (file_printf(ms, " (%d)", desc) == -1)
 571                                         return size;
 572                         } else if (desc / 10 % 10 > 0) {
 573                                 if (file_printf(ms, ".%d", desc / 10 % 10)
 574                                     == -1)
 575                                         return size;
 576                         }
 577                 } else {
 578                         if (file_printf(ms, " %d.%d", desc / 100000,
 579                             desc / 1000 % 100) == -1)
 580                                 return size;
 581                         if ((desc / 100 % 10 > 0) ||
 582                             (desc % 100000 / 100 == 0)) {
 583                                 if (file_printf(ms, " (%d)", desc) == -1)
 584                                         return size;
 585                         } else if (desc / 10 % 10 > 0) {
 586                                 if (file_printf(ms, ".%d", desc / 10 % 10)
 587                                     == -1)
 588                                         return size;
 589                         }
 590                 }
 591                 *flags |= FLAGS_DID_NOTE;
 592                 return size;
 593         }
 594
 595         if (namesz == 8 && strcmp((char *)&nbuf[noff], "OpenBSD") == 0 &&
 596             xnh_type == NT_OPENBSD_VERSION && descsz == 4) {
 597                 if (file_printf(ms, ", for OpenBSD") == -1)
 598                         return size;
 599                 /* Content of note is always 0 */
 600                 *flags |= FLAGS_DID_NOTE;
 601                 return size;
 602         }
 603
 604         if (namesz == 10 && strcmp((char *)&nbuf[noff], "DragonFly") == 0 &&
 605             xnh_type == NT_DRAGONFLY_VERSION && descsz == 4) {
 606                 uint32_t desc;
 607                 if (file_printf(ms, ", for DragonFly") == -1)
 608                         return size;
 609                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 610                 desc = elf_getu32(swap, desc);
 611                 if (file_printf(ms, " %d.%d.%d", desc / 100000,
 612                     desc / 10000 % 10, desc % 10000) == -1)
 613                         return size;
 614                 *flags |= FLAGS_DID_NOTE;
 615                 return size;
 616         }
 617
 618 core:
 619         /*
 620          * Sigh.  The 2.0.36 kernel in Debian 2.1, at
 621          * least, doesn't correctly implement name
 622          * sections, in core dumps, as specified by
 623          * the "Program Linking" section of "UNIX(R) System
 624          * V Release 4 Programmer's Guide: ANSI C and
 625          * Programming Support Tools", because my copy
 626          * clearly says "The first 'namesz' bytes in 'name'
 627          * contain a *null-terminated* [emphasis mine]
 628          * character representation of the entry's owner
 629          * or originator", but the 2.0.36 kernel code
 630          * doesn't include the terminating null in the
 631          * name....
 632          */
 633         if ((namesz == 4 && strncmp((char *)&nbuf[noff], "CORE", 4) == 0) ||
 634             (namesz == 5 && strcmp((char *)&nbuf[noff], "CORE") == 0)) {
 635                 os_style = OS_STYLE_SVR4;
 636         }
 637
 638         if ((namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0)) {
 639                 os_style = OS_STYLE_FREEBSD;
 640         }
 641
 642         if ((namesz >= 11 && strncmp((char *)&nbuf[noff], "NetBSD-CORE", 11)
 643             == 0)) {
 644                 os_style = OS_STYLE_NETBSD;
 645         }
 646
 647 #ifdef ELFCORE
 648         if ((*flags & FLAGS_DID_CORE) != 0)
 649                 return size;
 650
 651         if (os_style != -1 && (*flags & FLAGS_DID_CORE_STYLE) == 0) {
 652                 if (file_printf(ms, ", %s-style", os_style_names[os_style])
 653                     == -1)
 654                         return size;
 655                 *flags |= FLAGS_DID_CORE_STYLE;
 656         }
 657
 658         switch (os_style) {
 659         case OS_STYLE_NETBSD:
 660                 if (xnh_type == NT_NETBSD_CORE_PROCINFO) {
 661                         uint32_t signo;
 662                         /*
 663                          * Extract the program name.  It is at
 664                          * offset 0x7c, and is up to 32-bytes,
 665                          * including the terminating NUL.
 666                          */
 667                         if (file_printf(ms, ", from '%.31s'",
 668                             &nbuf[doff + 0x7c]) == -1)
 669                                 return size;
 670
 671                         /*
 672                          * Extract the signal number.  It is at
 673                          * offset 0x08.
 674                          */
 675                         (void)memcpy(&signo, &nbuf[doff + 0x08],
 676                             sizeof(signo));
 677                         if (file_printf(ms, " (signal %u)",
 678                             elf_getu32(swap, signo)) == -1)
 679                                 return size;
 680                         *flags |= FLAGS_DID_CORE;
 681                         return size;
 682                 }
 683                 break;
 684
 685         default:
 686                 if (xnh_type == NT_PRPSINFO && *flags & FLAGS_IS_CORE) {
 687                         size_t i, j;
 688                         unsigned char c;
 689                         /*
 690                          * Extract the program name.  We assume
 691                          * it to be 16 characters (that's what it
 692                          * is in SunOS 5.x and Linux).
 693                          *
 694                          * Unfortunately, it's at a different offset
 695                          * in various OSes, so try multiple offsets.
 696                          * If the characters aren't all printable,
 697                          * reject it.
 698                          */
 699                         for (i = 0; i < NOFFSETS; i++) {
 700                                 unsigned char *cname, *cp;
 701                                 size_t reloffset = prpsoffsets(i);
 702                                 size_t noffset = doff + reloffset;
 703                                 size_t k;
 704                                 for (j = 0; j < 16; j++, noffset++,
 705                                     reloffset++) {
 706                                         /*
 707                                          * Make sure we're not past
 708                                          * the end of the buffer; if
 709                                          * we are, just give up.
 710                                          */
 711                                         if (noffset >= size)
 712                                                 goto tryanother;
 713
 714                                         /*
 715                                          * Make sure we're not past
 716                                          * the end of the contents;
 717                                          * if we are, this obviously
 718                                          * isn't the right offset.
 719                                          */
 720                                         if (reloffset >= descsz)
 721                                                 goto tryanother;
 722
 723                                         c = nbuf[noffset];
 724                                         if (c == '\0') {
 725                                                 /*
 726                                                  * A '\0' at the
 727                                                  * beginning is
 728                                                  * obviously wrong.
 729                                                  * Any other '\0'
 730                                                  * means we're done.
 731                                                  */
 732                                                 if (j == 0)
 733                                                         goto tryanother;
 734                                                 else
 735                                                         break;
 736                                         } else {
 737                                                 /*
 738                                                  * A nonprintable
 739                                                  * character is also
 740                                                  * wrong.
 741                                                  */
 742                                                 if (!isprint(c) || isquote(c))
 743                                                         goto tryanother;
 744                                         }
 745                                 }
 746                                 /*
 747                                  * Well, that worked.
 748                                  */
 749
 750                                 /*
 751                                  * Try next offsets, in case this match is
 752                                  * in the middle of a string.
 753                                  */
 754                                 for (k = i + 1 ; k < NOFFSETS ; k++) {
 755                                         size_t no;
 756                                         int adjust = 1;
 757                                         if (prpsoffsets(k) >= prpsoffsets(i))
 758                                                 continue;
 759                                         for (no = doff + prpsoffsets(k);
 760                                              no < doff + prpsoffsets(i); no++)
 761                                                 adjust = adjust
 762                                                          && isprint(nbuf[no]);
 763                                         if (adjust)
 764                                                 i = k;
 765                                 }
 766
 767                                 cname = (unsigned char *)
 768                                     &nbuf[doff + prpsoffsets(i)];
 769                                 for (cp = cname; *cp && isprint(*cp); cp++)
 770                                         continue;
 771                                 /*
 772                                  * Linux apparently appends a space at the end
 773                                  * of the command line: remove it.
 774                                  */
 775                                 while (cp > cname && isspace(cp[-1]))
 776                                         cp--;
 777                                 if (file_printf(ms, ", from '%.*s'",
 778                                     (int)(cp - cname), cname) == -1)
 779                                         return size;
 780                                 *flags |= FLAGS_DID_CORE;
 781                                 return size;
 782
 783                         tryanother:
 784                                 ;
 785                         }
 786                 }
 787                 break;
 788         }
 789 #endif
 790         return offset;
 791 }
 792
 793 /* SunOS 5.x hardware capability descriptions */
 794 typedef struct cap_desc {
 795         uint64_t cd_mask;
 796         const char *cd_name;
 797 } cap_desc_t;
 798
 799 static const cap_desc_t cap_desc_sparc[] = {
 800         { AV_SPARC_MUL32,               "MUL32" },
 801         { AV_SPARC_DIV32,               "DIV32" },
 802         { AV_SPARC_FSMULD,              "FSMULD" },
 803         { AV_SPARC_V8PLUS,              "V8PLUS" },
 804         { AV_SPARC_POPC,                "POPC" },
 805         { AV_SPARC_VIS,                 "VIS" },
 806         { AV_SPARC_VIS2,                "VIS2" },
 807         { AV_SPARC_ASI_BLK_INIT,        "ASI_BLK_INIT" },
 808         { AV_SPARC_FMAF,                "FMAF" },
 809         { AV_SPARC_FJFMAU,              "FJFMAU" },
 810         { AV_SPARC_IMA,                 "IMA" },
 811         { 0, NULL }
 812 };
 813
 814 static const cap_desc_t cap_desc_386[] = {
 815         { AV_386_FPU,                   "FPU" },
 816         { AV_386_TSC,                   "TSC" },
 817         { AV_386_CX8,                   "CX8" },
 818         { AV_386_SEP,                   "SEP" },
 819         { AV_386_AMD_SYSC,              "AMD_SYSC" },
 820         { AV_386_CMOV,                  "CMOV" },
 821         { AV_386_MMX,                   "MMX" },
 822         { AV_386_AMD_MMX,               "AMD_MMX" },
 823         { AV_386_AMD_3DNow,             "AMD_3DNow" },
 824         { AV_386_AMD_3DNowx,            "AMD_3DNowx" },
 825         { AV_386_FXSR,                  "FXSR" },
 826         { AV_386_SSE,                   "SSE" },
 827         { AV_386_SSE2,                  "SSE2" },
 828         { AV_386_PAUSE,                 "PAUSE" },
 829         { AV_386_SSE3,                  "SSE3" },
 830         { AV_386_MON,                   "MON" },
 831         { AV_386_CX16,                  "CX16" },
 832         { AV_386_AHF,                   "AHF" },
 833         { AV_386_TSCP,                  "TSCP" },
 834         { AV_386_AMD_SSE4A,             "AMD_SSE4A" },
 835         { AV_386_POPCNT,                "POPCNT" },
 836         { AV_386_AMD_LZCNT,             "AMD_LZCNT" },
 837         { AV_386_SSSE3,                 "SSSE3" },
 838         { AV_386_SSE4_1,                "SSE4.1" },
 839         { AV_386_SSE4_2,                "SSE4.2" },
 840         { 0, NULL }
 841 };
 842
 843 private int
 844 doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num,
 845     size_t size, off_t fsize, int *flags, int mach)
 846 {
 847         Elf32_Shdr sh32;
 848         Elf64_Shdr sh64;
 849         int stripped = 1;
 850         void *nbuf;
 851         off_t noff, coff;
 852         uint64_t cap_hw1 = 0;   /* SunOS 5.x hardware capabilites */
 853         uint64_t cap_sf1 = 0;   /* SunOS 5.x software capabilites */
 854
 855         if (size != xsh_sizeof) {
 856                 if (file_printf(ms, ", corrupted section header size") == -1)
 857                         return -1;
 858                 return 0;
 859         }
 860
 861         for ( ; num; num--) {
 862                 if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
 863                         file_badseek(ms);
 864                         return -1;
 865                 }
 866                 if (read(fd, xsh_addr, xsh_sizeof) == -1) {
 867                         file_badread(ms);
 868                         return -1;
 869                 }
 870                 off += size;
 871
 872                 /* Things we can determine before we seek */
 873                 switch (xsh_type) {
 874                 case SHT_SYMTAB:
 875 #if 0
 876                 case SHT_DYNSYM:
 877 #endif
 878                         stripped = 0;
 879                         break;
 880                 default:
 881                         if (xsh_offset > fsize) {
 882                                 /* Perhaps warn here */
 883                                 continue;
 884                         }
 885                         break;
 886                 }
 887
 888                 /* Things we can determine when we seek */
 889                 switch (xsh_type) {
 890                 case SHT_NOTE:
 891                         if ((nbuf = malloc((size_t)xsh_size)) == NULL) {
 892                                 file_error(ms, errno, "Cannot allocate memory"
 893                                     " for note");
 894                                 return -1;
 895                         }
 896                         if ((noff = lseek(fd, (off_t)xsh_offset, SEEK_SET)) ==
 897                             (off_t)-1) {
 898                                 file_badread(ms);
 899                                 free(nbuf);
 900                                 return -1;
 901                         }
 902                         if (read(fd, nbuf, (size_t)xsh_size) !=
 903                             (ssize_t)xsh_size) {
 904                                 free(nbuf);
 905                                 file_badread(ms);
 906                                 return -1;
 907                         }
 908
 909                         noff = 0;
 910                         for (;;) {
 911                                 if (noff >= (off_t)xsh_size)
 912                                         break;
 913                                 noff = donote(ms, nbuf, (size_t)noff,
 914                                     (size_t)xsh_size, clazz, swap, 4,
 915                                     flags);
 916                                 if (noff == 0)
 917                                         break;
 918                         }
 919                         free(nbuf);
 920                         break;
 921                 case SHT_SUNW_cap:
 922                         if (lseek(fd, (off_t)xsh_offset, SEEK_SET) ==
 923                             (off_t)-1) {
 924                                 file_badseek(ms);
 925                                 return -1;
 926                         }
 927                         coff = 0;
 928                         for (;;) {
 929                                 Elf32_Cap cap32;
 930                                 Elf64_Cap cap64;
 931                                 char cbuf[/*CONSTCOND*/
 932                                     MAX(sizeof cap32, sizeof cap64)];
 933                                 if ((coff += xcap_sizeof) > (off_t)xsh_size)
 934                                         break;
 935                                 if (read(fd, cbuf, (size_t)xcap_sizeof) !=
 936                                     (ssize_t)xcap_sizeof) {
 937                                         file_badread(ms);
 938                                         return -1;
 939                                 }
 940                                 (void)memcpy(xcap_addr, cbuf, xcap_sizeof);
 941                                 switch (xcap_tag) {
 942                                 case CA_SUNW_NULL:
 943                                         break;
 944                                 case CA_SUNW_HW_1:
 945                                         cap_hw1 |= xcap_val;
 946                                         break;
 947                                 case CA_SUNW_SF_1:
 948                                         cap_sf1 |= xcap_val;
 949                                         break;
 950                                 default:
 951                                         if (file_printf(ms,
 952                                             ", with unknown capability "
 953                                             "0x%" INT64_T_FORMAT "x = 0x%"
 954                                             INT64_T_FORMAT "x",
 955                                             (unsigned long long)xcap_tag,
 956                                             (unsigned long long)xcap_val) == -1)
 957                                                 return -1;
 958                                         break;
 959                                 }
 960                         }
 961                         break;
 962
 963                 default:
 964                         break;
 965                 }
 966         }
 967         if (file_printf(ms, ", %sstripped", stripped ? "" : "not ") == -1)
 968                 return -1;
 969         if (cap_hw1) {
 970                 const cap_desc_t *cdp;
 971                 switch (mach) {
 972                 case EM_SPARC:
 973                 case EM_SPARC32PLUS:
 974                 case EM_SPARCV9:
 975                         cdp = cap_desc_sparc;
 976                         break;
 977                 case EM_386:
 978                 case EM_IA_64:
 979                 case EM_AMD64:
 980                         cdp = cap_desc_386;
 981                         break;
 982                 default:
 983                         cdp = NULL;
 984                         break;
 985                 }
 986                 if (file_printf(ms, ", uses") == -1)
 987                         return -1;
 988                 if (cdp) {
 989                         while (cdp->cd_name) {
 990                                 if (cap_hw1 & cdp->cd_mask) {
 991                                         if (file_printf(ms,
 992                                             " %s", cdp->cd_name) == -1)
 993                                                 return -1;
 994                                         cap_hw1 &= ~cdp->cd_mask;
 995                                 }
 996                                 ++cdp;
 997                         }
 998                         if (cap_hw1)
 999                                 if (file_printf(ms,
1000                                     " unknown hardware capability 0x%"
1001                                     INT64_T_FORMAT "x",
1002                                     (unsigned long long)cap_hw1) == -1)
1003                                         return -1;
1004                 } else {
1005                         if (file_printf(ms,
1006                             " hardware capability 0x%" INT64_T_FORMAT "x",
1007                             (unsigned long long)cap_hw1) == -1)
1008                                 return -1;
1009                 }
1010         }
1011         if (cap_sf1) {
1012                 if (cap_sf1 & SF1_SUNW_FPUSED) {
1013                         if (file_printf(ms,
1014                             (cap_sf1 & SF1_SUNW_FPKNWN)
1015                             ? ", uses frame pointer"
1016                             : ", not known to use frame pointer") == -1)
1017                                 return -1;
1018                 }
1019                 cap_sf1 &= ~SF1_SUNW_MASK;
1020                 if (cap_sf1)
1021                         if (file_printf(ms,
1022                             ", with unknown software capability 0x%"
1023                             INT64_T_FORMAT "x",
1024                             (unsigned long long)cap_sf1) == -1)
1025                                 return -1;
1026         }
1027         return 0;
1028 }
1029
1030 /*
1031  * Look through the program headers of an executable image, searching
1032  * for a PT_INTERP section; if one is found, it's dynamically linked,
1033  * otherwise it's statically linked.
1034  */
1035 private int
1036 dophn_exec(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
1037     int num, size_t size, off_t fsize, int *flags, int sh_num)
1038 {
1039         Elf32_Phdr ph32;
1040         Elf64_Phdr ph64;
1041         const char *linking_style = "statically";
1042         const char *shared_libraries = "";
1043         unsigned char nbuf[BUFSIZ];
1044         ssize_t bufsize;
1045         size_t offset, align;
1046
1047         if (size != xph_sizeof) {
1048                 if (file_printf(ms, ", corrupted program header size") == -1)
1049                         return -1;
1050                 return 0;
1051         }
1052
1053         for ( ; num; num--) {
1054                 if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
1055                         file_badseek(ms);
1056                         return -1;
1057                 }
1058
1059                 if (read(fd, xph_addr, xph_sizeof) == -1) {
1060                         file_badread(ms);
1061                         return -1;
1062                 }
1063
1064                 off += size;
1065
1066                 /* Things we can determine before we seek */
1067                 switch (xph_type) {
1068                 case PT_DYNAMIC:
1069                         linking_style = "dynamically";
1070                         break;
1071                 case PT_INTERP:
1072                         shared_libraries = " (uses shared libs)";
1073                         break;
1074                 default:
1075                         if (xph_offset > fsize) {
1076                                 /* Maybe warn here? */
1077                                 continue;
1078                         }
1079                         break;
1080                 }
1081
1082                 /* Things we can determine when we seek */
1083                 switch (xph_type) {
1084                 case PT_NOTE:
1085                         if ((align = xph_align) & 0x80000000UL) {
1086                                 if (file_printf(ms,
1087                                     ", invalid note alignment 0x%lx",
1088                                     (unsigned long)align) == -1)
1089                                         return -1;
1090                                 align = 4;
1091                         }
1092                         if (sh_num)
1093                                 break;
1094                         /*
1095                          * This is a PT_NOTE section; loop through all the notes
1096                          * in the section.
1097                          */
1098                         if (lseek(fd, xph_offset, SEEK_SET) == (off_t)-1) {
1099                                 file_badseek(ms);
1100                                 return -1;
1101                         }
1102                         bufsize = read(fd, nbuf, ((xph_filesz < sizeof(nbuf)) ?
1103                             xph_filesz : sizeof(nbuf)));
1104                         if (bufsize == -1) {
1105                                 file_badread(ms);
1106                                 return -1;
1107                         }
1108                         offset = 0;
1109                         for (;;) {
1110                                 if (offset >= (size_t)bufsize)
1111                                         break;
1112                                 offset = donote(ms, nbuf, offset,
1113                                     (size_t)bufsize, clazz, swap, align,
1114                                     flags);
1115                                 if (offset == 0)
1116                                         break;
1117                         }
1118                         break;
1119                 default:
1120                         break;
1121                 }
1122         }
1123         if (file_printf(ms, ", %s linked%s", linking_style, shared_libraries)
1124             == -1)
1125             return -1;
1126         return 0;
1127 }
1128
1129
1130 protected int
1131 file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf,
1132     size_t nbytes)
1133 {
1134         union {
1135                 int32_t l;
1136                 char c[sizeof (int32_t)];
1137         } u;
1138         int clazz;
1139         int swap;
1140         struct stat st;
1141         off_t fsize;
1142         int flags = 0;
1143         Elf32_Ehdr elf32hdr;
1144         Elf64_Ehdr elf64hdr;
1145         uint16_t type;
1146
1147         if (ms->flags & (MAGIC_MIME|MAGIC_APPLE))
1148                 return 0;
1149         /*
1150          * ELF executables have multiple section headers in arbitrary
1151          * file locations and thus file(1) cannot determine it from easily.
1152          * Instead we traverse thru all section headers until a symbol table
1153          * one is found or else the binary is stripped.
1154          * Return immediately if it's not ELF (so we avoid pipe2file unless needed).
1155          */
1156         if (buf[EI_MAG0] != ELFMAG0
1157             || (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1)
1158             || buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3)
1159                 return 0;
1160
1161         /*
1162          * If we cannot seek, it must be a pipe, socket or fifo.
1163          */
1164         if((lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) && (errno == ESPIPE))
1165                 fd = file_pipe2file(ms, fd, buf, nbytes);
1166
1167         if (fstat(fd, &st) == -1) {
1168                 file_badread(ms);
1169                 return -1;
1170         }
1171         fsize = st.st_size;
1172
1173         clazz = buf[EI_CLASS];
1174
1175         switch (clazz) {
1176         case ELFCLASS32:
1177 #undef elf_getu
1178 #define elf_getu(a, b)  elf_getu32(a, b)
1179 #undef elfhdr
1180 #define elfhdr elf32hdr
1181 #include "elfclass.h"
1182         case ELFCLASS64:
1183 #undef elf_getu
1184 #define elf_getu(a, b)  elf_getu64(a, b)
1185 #undef elfhdr
1186 #define elfhdr elf64hdr
1187 #include "elfclass.h"
1188         default:
1189             if (file_printf(ms, ", unknown class %d", clazz) == -1)
1190                     return -1;
1191             break;
1192         }
1193         return 0;
1194 }
1195 #endif